Support list.__imul__

Author: adrian17

tests/snippets/list.py

@@ -14,6 +14,10 @@
 assert x * 0 == [], "list __mul__ by 0 failed"
 assert x * -1 == [], "list __mul__ by -1 failed"
 assert x * 2 == [1, 2, 3, 1, 2, 3], "list __mul__ by 2 failed"
+y = x
+x *= 2
+assert y is x
+assert x == [1, 2, 3] * 2
 
 # index()
 assert ['a', 'b', 'c'].index('b') == 1

vm/src/obj/objlist.rs

@@ -395,6 +395,12 @@ impl PyListRef {
         vm.ctx.new_list(new_elements)
     }
 
+    fn imul(self, counter: isize, _vm: &VirtualMachine) -> Self {
+        let new_elements = seq_mul(&self.elements.borrow(), counter);
+        self.elements.replace(new_elements);
+        self
+    }
+
     fn count(self, needle: PyObjectRef, vm: &VirtualMachine) -> PyResult<usize> {
         let mut count: usize = 0;
         for element in self.elements.borrow().iter() {
@@ -823,6 +829,7 @@ pub fn init(context: &PyContext) {
         "__iter__" => context.new_rustfunc(PyListRef::iter),
         "__setitem__" => context.new_rustfunc(PyListRef::setitem),
         "__mul__" => context.new_rustfunc(PyListRef::mul),
+        "__imul__" => context.new_rustfunc(PyListRef::imul),
         "__len__" => context.new_rustfunc(PyListRef::len),
         "__new__" => context.new_rustfunc(list_new),
         "__repr__" => context.new_rustfunc(PyListRef::repr),